There is a type bug because the return statement: return ret < 0 ? ret : recv_cnt; will not return negatives on 64bit systems. The problem is that the function returns ssize_t types, while "ret" is int and "recv_cnt" is a u32. The negative values are type promoted to u32 and returned as positive values instead of negative error codes. Fixes: 81cc7e51c4f1 ("drm/mediatek: Allow commands to be sent during video mode") Signed-off-by: Dan Carpenter <error27@xxxxxxxxx> --- drivers/gpu/drm/mediatek/mtk_dsi.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c index 7d5250351193..8e99981ca0e1 100644 --- a/drivers/gpu/drm/mediatek/mtk_dsi.c +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c @@ -1016,12 +1016,12 @@ static ssize_t mtk_dsi_host_transfer(struct mipi_dsi_host *host, const struct mipi_dsi_msg *msg) { struct mtk_dsi *dsi = host_to_dsi(host); - u32 recv_cnt, i; + ssize_t recv_cnt; u8 read_data[16]; void *src_addr; u8 irq_flag = CMD_DONE_INT_FLAG; u32 dsi_mode; - int ret; + int ret, i; dsi_mode = readl(dsi->regs + DSI_MODE_CTRL); if (dsi_mode & MODE) { @@ -1070,7 +1070,7 @@ static ssize_t mtk_dsi_host_transfer(struct mipi_dsi_host *host, if (recv_cnt) memcpy(msg->rx_buf, src_addr, recv_cnt); - DRM_INFO("dsi get %d byte data from the panel address(0x%x)\n", + DRM_INFO("dsi get %zd byte data from the panel address(0x%x)\n", recv_cnt, *((u8 *)(msg->tx_buf))); restore_dsi_mode: -- 2.39.1